The ever-increasing demand for smaller sized mobile devices, such as cell phones, digital cameras, etc., correspondingly triggered a growing need for a smaller sized photography module, comprising elements such as an optical imaging lens, a module housing unit, and an image sensor, etc., contained therein. Size reductions may be obtained from various aspects of the mobile devices, which includes not only the charge coupled device (CCD) and the complementary metal-oxide semiconductor (CMOS), but also the optical imaging lens mounted therein. When reducing the size of the optical imaging lens, however, achieving good optical characteristics become a challenging problem.
Both U.S. Pat. No. 7,480,105 and Japan Patent Publication No. 4197994 disclose an optical imaging lens constructed with an optical imaging lens having five lens elements, wherein the length of the optical imaging lens, from the object-side surface of the first lens element to the image plane, reaches 8 mm, which is too long for smaller sized mobile devices. Therefore, there is a need to develop an optical imaging lens which is capable of placing five lens elements therein, with a shorter length, while also have good optical characteristics.